1. Field of the Invention
The present invention relates to an apparatus employed to remove a fluted cup of lightweight material from a stack of a plurality of similar cups tightly nested together.
2. Description of the Related Art
Apparatus and machines known for fabricating, manipulating and processing fluted cups constructed of paper and other light weight materials are described in the following patents:
U.S. Pat. No. 3,907,161 to Martin discloses an apparatus for denesting stacked packaging trays having a suction gripper that moves into engagement with the outer most tray in a stack of trays, moving the outer most tray from the stack through an opening in the magazine that holds the stack.
U.S. Pat. No. 4,106,397 to Amberg et al. discloses a denesting cup having a head formed from a sheet-like plastic material with a plurality of vacuum holes formed in the head to engage the inner portions of the stack.
U.S. Pat. No. 4,135,619 to Cerboni discloses a device for collecting and transferring confectionery products, and which has a series of vacuum heads that pick the confectionery products from a conveyor.
U.S. Pat. No. 4,919,587 to Tashiro et al. discloses a device having a denesting head to remove cups one at a time from a stack of cups and place them on a conveyor.
U.S. Pat. No. 4,967,930 to Koltze discloses a device for separating conical tubes stored in a nested stack by means of two gripping ring assemblies arranged to engage the last tube in the stack and the next to the last tube in the stack, in order to separate the last two.
U.S. Pat. No. 5,064,093 to Davis et al. discloses a device having a plurality of elongated helical screws for separating trays of a plurality of cups.
U.S. Pat. No. 5,172,922 to Kowaleski et al. discloses a self aligning vacuum nozzle used for removing or lifting products in automated assembly operations. A nozzle tip pivots to align with surfaces that are not planar.
U.S. Patent No. 5,668,008 to Hansch discloses a suction device which has a swiveling head for gripping an article, the suction transmitted evenly through the angle of adjustment of the head in order to apply the suction that grips the article.
In food production industries, a fluted cup made from paper or a paper backed foil is used to hold the comestible (food product). The fluted cups are transported to different locations as a stack of a multiplicity of the cups. The cups often arrive at the manufacturing facility tightly nested together as a compacted stack of a multiplicity of individual cups.
The above is a cost-effective way to transport the stacked cups, provides for maintaining the uniform structure of the individual cups, and deters against crushing to which the cups are susceptible during transport. At the food production facility, the stack of nested cups must be separated into discrete units for further processing and into which the food product such as cupcakes or bakery dough, is to be deposited. Machinery is employed to reduce the labor intensive aspect of separating the individual cups from the nested stack prior to filling the cups. However, the known devices discussed above have many disadvantages for accomplishing the task.
First, conventional picker heads which employ suction do not effectively and as quickly separate and remove each individual fluted cup from the stack. Secondly, when they are removed, it is sometimes in groups of two or more, not individually as required. Thirdly, known picker heads deform the fluted cup and in certain instances, bend the cups so that they do not maintain the circular or desired shape that they were shipped in and into which the food product will be disposed. In addition, known picker head devices are constructed to only pull an individual fluted cup from the remaining stack, as opposed to providing a dual action, as in the present invention of pulling an individual cup from the stack and pushing or exerting a force on the stack to separate the stack from the individual cup to be removed.
It is therefore an object of the present invention to provide a vacuum apparatus and method for denesting objects for use with stacks of objects such as paper cups which are tightly packed together.
It is an object of the present invention to provide a vacuum apparatus which is constructed and arranged to reduce the labor intensive aspect of separating individual cups from a nested stack of a multiplicity of cups.
It is another object of the present invention to provide a vacuum apparatus which pulls an individual fluted cup from a stack of a multiplicity of the cups and simultaneously exerts a force on the stack to separate the individual cup from the remaining stack.
It is another object of the present invention to provide a vacuum apparatus which channels the airflow during the vacuum formed to cause the fluted cup to conform to a vacuum head of the apparatus which does not deform the shape of the fluted cup.
It is another object of the present invention to provide a vacuum apparatus which is provided with ejection means to displace a cup at the vacuum picker head of the apparatus for subsequent processing.
It is another object of the present invention to provide a vacuum apparatus having an exterior surface area constructed and arranged to substantially reduce stress exerted on the fluted cup during the vacuum operation.
It is another object of the present invention to provide a vacuum apparatus having a base portion constructed and arranged for supporting an open end of each fluted cup to facilitate the vacuum operation and ejection of the cup from the vacuum apparatus without deforming the structure of the fluted cup.
It is another object of the present invention to provide a vacuum apparatus having a picker head portion with a plurality of depressions for increasing the surface area of the head portion to facilitate a more controlled vacuum effect upon the fluted cup.
It is another object of the present invention to provide a vacuum apparatus having a vacuum picker head coacting with a vacuum guide plate or base plate for control of the vacuum picking of each individual fluted cup from a stack of nested cups.
It is another object of the present invention to provide a vacuum apparatus having a plurality of vacuum picker heads constructed and arranged for coaction with a vacuum guide or base plate upon which a plurality of nested stacks of fluted cups are arranged in registration with the corresponding plurality of vacuum picker heads.
To accomplish the foregoing objects, the vacuum picker apparatus according to the present invention includes a vacuum picker head with concave surface areas, each being preferably xc2xdxc2x0 reverse angle, and each surface area having a hole therethrough that allows for a vacuum to be formed at the picker head. When the vacuum is formed, the side wall of the fluted cup is actually drawn inside the overall circumference of the head at each concave surface area to provide for an effective seal to hold the cup to the picker head, which reduces deformation of the cup and facilitates its extraction for further processing.
Another feature of the present invention is a protective ring or skirt having spaced apart notches through which apertures are formed to direct a thrust of air in a direction to force an individual cup being denested from the remaining stack of cups.
The dual action of the vacuum picker apparatus of the present invention extracts an individual cup from a stack of cups and directs a blast of air at the stack to facilitate removal of the individual cup from the stack.